CVE-2026-46147
published 2026-05-28CVE-2026-46147: In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu() Two bugs exist in…
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix pin leak and publication ordering in __pkvm_init_vcpu()
Two bugs exist in the vCPU initialisation path:
1. If a check fails after hyp_pin_shared_mem() succeeds, the cleanup
path jumps to 'unlock' without calling unpin_host_vcpu() or
unpin_host_sve_state(), permanently leaking pin references on the
host vCPU and SVE state pages.
Extract a register_hyp_vcpu() helper that performs the checks and
the store. When register_hyp_vcpu() returns an error, call
unpin_host_vcpu() and unpin_host_sve_state() inline before falling
through to the existing 'unlock' label.
2. register_hyp_vcpu() publishes the new vCPU pointer into
'hyp_vm->vcpus[]' with a bare store, allowing a concurrent caller
of pkvm_load_hyp_vcpu() to observe a partially initialised vCPU
object.
Ensure the store uses smp_store_release() and the load uses
smp_load_acquire(). While 'vm_table_lock' currently serialises the
store and the load, these barriers ensure the reader sees the fully
initialised 'hyp_vcpu' object even if there were a lockless path or
if the lock's own ordering guarantees were insufficient for nested
object initialization.
Affected
6 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | < 6.18.30 | 6.18.30 |
| linux | linux | < 7.0.7 | 7.0.7 |
| linux | linux | >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7d3c27b54253cda91dc4d2c1bfc109c490837ab9 | 7d3c27b54253cda91dc4d2c1bfc109c490837ab9 |
| linux | linux | >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6d69c0ed978f7f0efd053fc98390f25ab77c1aea | 6d69c0ed978f7f0efd053fc98390f25ab77c1aea |
| linux | linux | >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 73b9c1e5da84cd69b1a86e374e450817cd051371 | 73b9c1e5da84cd69b1a86e374e450817cd051371 |
| linux | linux_kernel | — | — |